dedifferentiated chondrosarcoma
A high-grade malignant bone tumor containing both low-grade chondrosarcoma and high-grade non-cartilaginous sarcoma components.
Full Definition
Dedifferentiated chondrosarcoma is an aggressive variant of chondrosarcoma characterized by the presence of both conventional low-grade chondrosarcoma and high-grade non-cartilaginous sarcoma within the same tumor. This biphasic tumor typically occurs in patients over 50 years of age and most commonly affects the pelvis, femur, and humerus. The dedifferentiated component may consist of osteosarcoma, fibrosarcoma, or undifferentiated pleomorphic sarcoma. The prognosis is significantly worse than conventional chondrosarcoma due to the aggressive nature of the high-grade component and its propensity for metastasis.
Usage
Usage note: Always specify the high-grade component type when identified histologically.
In Context
- "Biopsy revealed dedifferentiated chondrosarcoma with high-grade spindle cell areas." — Pathology report
- "The patient's pelvic mass showed features of dedifferentiated chondrosarcoma on MRI." — Imaging report